The invention relates to a combine harvester having a driver assistance system, which regulates the spreading on the ground of a crop flow exiting the combine harvester
The non-grain proportion harvested by a combine harvester during the harvesting operation is often spread directly on the harvested territory, e.g., to improve the soil quality. In this connection, it is important that the spread crop has qualities that permit it to decay easily, thereby ensuring that the nutritive components thereof are available in the subsequent vegetation phase. Optimal decay is achieved when the crop spread on the ground is in suitably short pieces and is spread homogeneously across the working width of the combine harvester.
Diverse solutions, which are intended to satisfy these requirements, are known from the prior art. For example, EP 0 685 151 discloses a system in which the wind conditions in the region of the crop spreading device of the combine harvester are determined and the discharge behavior of the spreading device is regulated according to the wind conditions. Such a system has the advantage that a spreading of the broken straw-chaff mixture conveyed out of the combine harvester that is non-uniform due to cross winds is avoided or at least reduced.
EP 1 790 207 discloses a system in which the spreading of the crop flow exiting the combine harvester in the rear region thereof is regulated depending on the position of the crop edge. Such a system ensures that the portion of remaining material to be spread on the ground is not discharged into a crop yet to be harvested, since this would have the disadvantage that already-threshed crop would be picked up again by a combine harvester.
Reference also is made to EP 1 514 466, which discloses a combine harvester having a chopper and spreading unit and an infrared camera in the rear region thereof. The infrared camera senses the quality of the distribution of the broken straw-chaff mixture deposited on the ground on the basis of the detected temperature distribution, wherein higher temperatures are an indicator of a greater material feed height. On the basis of the determined temperature change, kinematic parameters of the crop chopping (or shredding) and spreading device are adapted such that a substantially uniform temperature distribution sets in across the spreading width, which ultimately serves as an indicator of homogeneous crop spreading.
All the described systems have the disadvantage that these typically only ever evaluate one defined parameter in order to determine the spreading quality. Such a system is incapable of detecting complex interrelationships between highly diverse parameters that influence the homogeneity of crop spreading.
The problem addressed by the invention is therefore that of avoiding the described disadvantages of the prior art and, in particular, of providing a driver assistance system, which better detects and accounts for the complex interrelationships between highly diverse parameters, which influence the spreading of the crop on the ground.